Postoperative pseudomeningoceles represent extradural fluid collections of CSF content communicating with the subarachnoid space through small dural tears. Chronic CSF leakage may lead to paraspinal pseudocyst formation with surrounding reactive changes. 

Pseudomeningoceles may very rarely occur following lumbar laminectomy, with an incidence of around 1-2%. 

Nerve root herniation may occur within the cystic cavity, and this, in turn, may lead to radicular symptoms and potentially irreversible nerve damage.